THE BAD NEWS: The "atmospheric river" pattern of this last storm could be a sign of things to come. At one point, the storm's moisture plume reached all the way to the Equator! Add extra fuel from a resurgent El Nino, bring in some good ole' Siberian High pressure systems - and by end of next month, a stormy sequence may be rolling once again across the Eastern U.S.

11/27/14 - In the wake of a storm that brought a White Thanksgiving to some not seen in 25 years -- we would like to introduce a special opportunity for all our readers across the Mid-Atlantic. Whether you are a life-long snow enthusiast, a decision-maker in your organization, or a busy parent, we know there are times you need access to specifics on what the weather will do next.That's where the club comes in, and we're excited to reveal what is planned for this program!

Request a FREE Powderhound Insider Newsletter with details on the December pattern and beyond...

2:36 PM EST 11/26 - After a brief lull following the mid-morning snow BOOM, some areas are seeing snowfall restart. The good news is that the "back edge" is approaching, but the bad news is it may come with a final dump of snow between 4-5 PM for the I-95 corridor.

The storm may end the way it started, strangely, just backwards: A rush of snow, then rain showers.

After the precip clears, temps should begin dropping on northwest winds - and lows of 27-30 in northern and western counties could produce refreezing of standing water.

HOLIDAY TRAVELING?We suggest you get going as quickly as possible, before the back edge brings a final grand finale. We bid Godspeed to all travelers and our best wishes for a smooth trip.

THANKSGIVING DAY: Cold and breezy, which will help evaporate standing water, but will make for a raw day. Highs holding in the upper 30s to 40 F.

NEED BETTER ACCESS TO OUR TEAM? We have a solution for those looking to get the inside track an seek life beyond Facebook. It's called the "Powderhound Club" and by joining, when "we know, you'll know." No more weather surprises, get rapid access to our info to aid in those tough decisions, and we'll work the storms together!

SNOW WILL MIX WITH RAIN FROM NORTHWEST TO SOUTHEAST THIS MORNING. EXCEPT FOR AREAS ALONG AND EAST OF I-95, WHICH STAYS RAIN/SLEET UNTIL 1-2 PM.

NORTH AND WEST OF I-95, EXPECT HEAVY WET SNOW STARTING NO LATER THAN 11 AM, CREATING DANGEROUS VISIBILITY ISSUES, EVEN IF ACCUMULATION IS SLOW.

PARENTS OF STUDENTS IN SCHOOL DISTRICTS CLOSING EARLY ARE REMINDED THAT DANGEROUS DRIVING CONDITIONS MAY EXIST DURING DISMISSAL AND TRANSPORT HOME. PLEASE MAKE EVERY ATTEMPT TO SEE THAT YOU ON TIME FOR PICKUP, OR ARE HOME BEFORE ELEMENTARY-AGE CHILDREN ARRIVE.

For those still unconvinced this system will surprise many of us with significant heavy snow, take note of the point of origin for much of the moisture heading our way:

- From the Atlantic? Some, not all.

- From the Gulf of Mexico. Sort of.- How about the East Pacific? The real answer: ALL THREE. This system is tapping into moisture sources from three bodies of water, starting in the East Pacific, then scooping up more in the Gulf, and finally tapping Atlantic sources once the winds shift northeast.TAKE A LOOK FOR YOURSELF! Below is a NOAA Water Vapor image for the Caribbean, E Pacific and western Atlantic, showing an unbroken tropical feed of moisture 2,000 miles long originating from the West coast of Mexico-- all the way across the Gulf of Mexico, and all the way north to your door. THAT's why we're confident this system has potential to be significant.

WHAT TO LOOK FOR:This is, as they would say, a "fluid situation." We present several look-fors that will help you detect in the AM hours which direction this storm forecast will go-- either BOOM or BUST. Our thanks to Forecaster Troy from the University of Maryland, College Park for this assessment:

1. If temperatures are still well above freezing by noon time, snowfall accumulation could be less than expected.

2. If you see snowing coming down heavily in the morning hours near I-95, this indicates the "bust scenario" of colder temperatures is playing out. Thus, the storm is likely to over-perform, exceeding current accumulation forecasts.

3. If the storm is stronger than forecasted, higher snowfall rates would also produce a more rapid drop in temperatures. This is known as "evaporative cooling" in which the formation of snowflakes from water vapor actually chills the surrounding air-- leading to more snow, falling faster and sticking easier because there is more of it to overcome warm surfaces.

FINAL SNOWFALL MAP

BUST SCENARIO 1:TOO WARM! (75% chance) With so much warm air in place ahead of this storm, it is "on its own" to cool down the atmosphere enough to have "snow producing "temperatures.

In this scenario, those in the C-2” zone would see nothing, the 2-4” zone would struggle to get a coating, and the 3-6” zone could only pick up a couple of inches. There are two sub-possibilities here:

A) Surface temperatures don’t cool down below the mid 30s. We end up with a “white rain” of snow that can’t stick, or if the warm layer is deep enough, just rain. This could move across much of the metro areas during the heaviest precipitation, preventing accumulating snow.

B) Warm air noses in in the mid-troposphere during the height of the storm. This flips precipitation along I-95 to all rain instead of a mix.

BUST SCENARIO 2:OVER-PERFORMING COLD! (25% chance) On the flip side, we could have abundant evaporational cooling that puts temperatures at 31 or 32° instead of a few degrees higher.

That small difference means that much more snow can stick. In this scenario, western areas could see up to 8” , the 2-4” zone could be more like 4-6” , and the C-2” zone sees up to 4”

BOTTOM LINE? Sun Tzu was right, if you know the ground, and know the weather, then your victory will be total. In less than 12 hours we all shall find out who shall be victorious in the call for this first winter storm of our 11th season of forecasting!

Special FREE teleconference briefing available Tuesday late AM and early PM to ask our forecasters your questions about the storm. Send us a message to winter(at) footsforecast.org to register for the call. Indicate what weather information about this event would aid your decision-making.

Four (4) time slots will be available, pick any of them at your convenience.

For companies or organizations, denote one representative who can report back to your group. A briefing package will be sent Tuesday AM with call-in details.

OVERVIEW (By Forecaster Mike Natoli) Regardless of heavy rain or snow, we all are likely to see a disruptive storm moving up the East coast at the very least.

We have refined our ideas to two scenarios depending on surface temperatures. Temperatures will be marginal, near or slightly above freezing, which will initially make snow accumulation difficult. However, as computer models have been projecting for the past 24 hours, high snow fall rates may overcome warm surfaces and create a surprise situation Wednesday afternoon.

We remain cautious on this storm, because a slight shift of precip arrival or type over just 2 hours on Wednesday morning will impact the entire day's forecast. If we decide we need to make a snow accumulation forecast, that will be issued either later tonight or Tuesday morning. Until then we have narrowed the potential outcomes to TWO SCENARIOS, outlined in the next section.

10:45 AM EST 11/24 UPDATED: LATEST SNOWFALL PROBABILITIES from the NOAA Weather Prediction Center should give ANYONE pause if you plan to travel Wednesday, or are in essential services. Teachers, this is a great opportunity to show your students why understanding the legend on a map is critical to good decision-making.

INCREASING PROBABILITY OF AT LEAST 8" NORTH AND WEST OF THE I-95 CORRIDOR. As noted below in the green banding. Source: NOAA WPC Winter Suite

THE TAKEAWAY?We don't care that it's going to be 70 F today in some places. That's the ruse. Don't fall for it. How many thousands of travelers on Wednesday will allow today's aberrant warm weather to fool them into false security that"roads will be just fine, sheesh. Not like it's January, right?" WRONG: The issue WILL NOT be snow covered roads, it will be VISIBILITY due to heavy wet snow combined with high volume traffic. One person decides to slow to a crawl on 95 at 3 PM in the snow, and BOOM. There goes your holiday weekend. Think about it. Plan ahead. Consider how you can adjust your plans now before reality hits and its too late.

OUR FEAR: Unless something changes drastically in the storm track trends, this series of unfortunate events on the Wednesday before Thanksgiving could become the worst day of mass travel in modern times, if we have a repeat of January 26, 2011.

1:05 PM 11/23(By the Kentucky & Winter Stormcast Teams)Although the Thanksgiving holiday period is finally arriving, Mother Nature shows no signs of taking time off as the potential is increasing for a significant weather event that could snarl one of the busiest travel days of the year.

THE SITUATION: Our team first identified the potential for a "White Thanksgiving" in an October 25 post, due in part to data showing a record high snow-cover for Siberia and the downstream effects that large Arctic highs would have coming across the Pole. Now in present day, numerous medium range model runs support a significant winter storm occurring on Wednesday into Thanksgiving morning near the East coast.

The areas which may see notable to significant impacts from this system extend from South Carolina to the Mid-Atlantic, into the Northeast all the way to Maine.

As with all storm forecasts more than 72 hours out, we expect considerable variance between forecasted data and outcomes, until shortly before the event begins.

The timing of this system creates additional concern for the traveling public, hence we are outlining scenarios early to help identify which pattern will prevail.

SCENARIO A:OUR GOOSE IS COOKED.An area of low pressure develops in the northern Gulf and moves along the East coast, bringing Gulf moisture while drawing in Atlantic moisture. The system would tap cold air from a snow-cover influenced surface high in western PA/NY.

This track would hug the shoreline, bringing heavy rain and tidal flooding to coastal communities and heavy snow in the interior.

As temperatures fall into the 30s through the Mid-Atlantic and Northeast, rain would change to snow in the major cities and continue heavy overnight, producing a major snowfall to a majority of the Northeastern states.

SCENARIO B:BETTER LEAVE EARLY ANYWAY.The storm develops weaker and further east than in Scenario A. This would produce far less precip for the Carolinas, Mid-Atlantic and Northeast.

However, colder air will be more available, as northwest flow would rush in behind the departing storm. Coastal areas would see a cold rain or wet snow that has trouble sticking until after nightfall Wednesday.

The bulk of energy would affect northern states, especially New England while the Mid-Atlantic is only brushed with light accumulations.

SCENARIO C:CANCEL THE SNOWSUIT SEARCH!Strength and influence of the Great Lakes system on Tuesday nudges any coastal Low pressure away from the eastern seaboard, in tandem with surface high pressure to the north.

This would bring only brief light precipitation to coastal areas, little or no precipitation to major cities and minimal impacts on Thanksgiving travel.

Our Winter Stormcast Team will be frequently monitoring the latest changes and updating here as data becomes available. Our next update is planned for Monday where we will narrow the scenarios to 2 options and begin discussing precip and snowfall ideas.

Saturday, November 22, 2014

6:55 PM EST 11/22 - UPDATED - Scenario Map and Storm Track Probability posted below. Text of the scenarios will be added on Sunday. By Monday we will narrow to 2 tracks, with preliminary snowfall ideas by Monday night and a snowmap by Tuesday afternoon.

3:42 PM EST 11/22 - Early this week, we posted a report hoping that the weather would not "be a turkey" for the upcoming holiday weekend. However, the pre-winter pattern indicates Mother Nature did receive our memo from October 25*, and appears determined to deliver the first widespread White Thanksgiving to the Mid-Atlantic and Northeast since 1989. (*Hint: It's the post where we said this year, there's better chance of a White Thanksgiving than a White Christmas."

TEAM STATEMENT: Our composite analyses of several well-known computer models suggests a potentially significant winter weather event may affect much of the East coast for the Wednesday-Thursday period. The timing of this storm could seriously disruptive the Wednesday afternoon and evening holiday travel, if present indications for that time period do not change appreciably.(Left: Liquid forecasts from NOAA as of Saturday 11/22 show a large swath of precip to affect the East coast Wed night through Friday)

KEY TAKEAWAYS

The system is still 4-5 days away from affecting any of us. But the untimely prospect of a serious storm arriving on the busiest travel days of the year warranted an early heads up.

If traveling by air on Wednesday night anywhere along the East coast, it might be strategic to contact the airline now and be aware of your options if the situation deteriorates.

It is too early to project when and where snow will fall Wednesday. If planning to travel by vehicle, consider now alternate times or routes you could take if snow develops Wed night in your area or along your route.

TRACK: Our three-outcome graphic above depicts the likely paths, and by Sunday-Monday we can narrow this down to the one solution we expect to be most probable. We emphasize that much can change at 120 hours prior to a storm. Slight shifts can produce major differences, and with a lot of air movement and liquid in play, it warrants close attention.

The Takeaway: We understand how serious this situation would be for millions of people all across the country and around the world. In the words of our headline, this really is cutting it kinda close, in how it could completely disrupt the travel plans of everyone depending on air travel in or out of the Northeast. It's not appropriate to cancel your plans based on a 5-day forecast, but it is reasonable to contact your airline and learn your options if the situation sours quickly on Wednesday.

TEMPS: Despite an expected spike into the 50s and 60s by Tuesday, another push of Arctic air will return to the region. Some computer scenarios show a cold rain on Wednesday changing to snow before nightfall. Were the coastal low to develop as shown on Tue-Wed, it would tap a large reservoir of nearby cold air due to the recent heavy snowcover in the Great Lakes to New York state. The European model, notable for accuracy in long range calls from recent winters, shows sub 34 F temps from Virginia north by 7 PM Wednesday.

The Takeaway:Were these temps to occur during a "nor-easter" setup, the result would be wind-whipped heavy snow to hit major East coast interstates of the Northeast corridor at the absolute worst possible time: Wednesday night.

LIQUID: The NOAA Weather Prediction Center's latest liquid projections, (shown above) prepared by actual meteorologists using input from several model sources to convey what we call a "broad brush" look at what's possible. A general 0.50" to 0.75" of liquid is, at this point, the most probable outcome for the I-95 corridor.

The Takeaway:A slight shift to the west by Wednesday would bring much heavier precipitation, and possibly, heavy snow with low visibility, to the expected high traffic volume areas of the map.

NEXT UPDATE: Our team will keep close watch on this developing story, and post updates in the early morning and early evening, with a mid-day reassessment each day.

Wednesday, November 19, 2014

UPDATED 11/22/2014 - If long range projections are on target, it appears Mother Nature got our memo from 9/25 when we anticipated that a "White Thanksgiving was more likely this year than a White Christmas." The European and US Global Forecast System model printouts, though just at the 120-hour mark, are leaning toward a more snowy result for the mid-Atlantic Wednesday night into Thanksgiving Day. With this event potentially impacting the busiest travel period of the year, we are preparing an overview of the possible hazards, timing and intensity for posting here on Sunday.

NOAA SURFACE MAP PROJECTION FOR
NEXT MON 11/25 AS OF WED 11/19.

11/19/2014- We know it's coming on quickly, there's nothing anyone can do about it, and there are some who wish it would never happen.

It's not the raucous Midwest-Great Lakes storm to roar through the heartland next week...

Rather, it is the sometimes dreaded Thanksgiving week travel and the shopping frenzy to follow -- that plunges us all headlong into a spin cycle of insanity. Toss in a "little weather" to the airline adventure and whoop! There it is: Harried parents and woesome children at long ticket counter lines... and so on.

But thanks to taxpayer-funded technology, we have access to this really cool technology from the US Department of Commerce that actually SHOWS, like, a glimpse of what things could be like next week as the holiday travel season launches forth. This way, it's not a mystery to anyone:

MONDAY: A vigorous storm system will develop in the southern plains and head for the Great Lakes. On east side of the storm, temperatures Mon-Tue in the Eastern U.S. will begin rebounding to seasonal levels. On the west side of the storm, as noted by the cold front above, conditions will be -- you guessed it -- STORMY! Strong winds, heavy rain and then potentially heavy snow.

TUESDAY: We already hear Airport Operators saying, "Can we just get that thing outta here before Wednesday?" Well try, my friends, we'll try. However, it is reasonable to expect flight delays may begin Tuesday and spread into Wednesday because of the front sweeping across the Eastern states. Places that face potential travel disruptions may include the I-95 corridor from Richmond to New York as a series of Lows could develop and move north along the cold front. Indications point to this being more of a "wet" day than a "white" one, as temperatures should stay above freezing. We'll monitor closely of course as the day approaches.

WEDNESDAY: Arrival of the dreaded big travel day. Early interpretation from NOAA's Day 7 map, while still quite distant in weather time concerns, suggests the hope of travelers may pan out: High pressure looks to reestablish behind the front in the Eastern US, stabilizing the pattern from storminess for Wed into Thanksgiving Day.

Until then, think ahead to how you would alter your plans for travel on Wed 11/26 IF you had to, unless the weather decides to cut us a break this year and not be a turkey after all.

Foot's Forecast is not the work of one person, a single idea, or one team. It was founded in a science classroom of a working class community. Over the past 10 years, the contributions of many have made it much more.

Today, it is a collaborative investment of passion by talented young adults in unlikely places, united by their drive to communicate science with the public. They are intelligent, dynamic and funny. They are healthy, handsome, and pretty. (Weather people always are, it must be an outdoor thing.)

But above it all ...

.. they are inspirational evidence that, despite what the media may say about the youth of America, there are still many hard-working, reliable contributors to our society who make a difference in countless lives every day.

The "Alex From Target" (NYT article) phenomenon of the past month is an interesting look at how and why we use social media today. We are excited that a dedicated, down-to-earth student has earned some credit on behalf of many unsung youth heroes who go about their work and school in a humble way.

Although winter is descending early across America, the lives of our forecasters are brimming hot with potential, highly-marketable skills, and an attitude of service that I think any employer should break down our door to get these rockstars on THEIR team.

And if it was known truly knew how talented these servants really are, employers would be contacting me for referrals. So over time we are going to paint the true story about each of our stars, and if you're interested in seeing a resume from any of them, send me a note: team@footsforecast.org.